President Barack Obama on Wednesday warned Wall Street and the nation that the current crisis over raising the debt ceiling could be the one that finally sends the U.S. economy off a cliff.

“This time’s different,” he said in an interview with CNBC. “I think they should be concerned.”

“It is not unusual for Democrats and Republicans to disagree … but when you have a situation in which a faction is willing to potentially default on U.S. government obligations, then we’re in trouble,” he added.

The president’s comments came ahead of an early evening meeting with congressional leaders and reflected a more frustrated public tone, as he said he has become “exasperated” with Republicans in Washington.

“I think it’s fair to say that during the course of my presidency, I have bent over backwards to work with the Republican Party and have purposely kept my rhetoric down,” he said. “I think I’m pretty well-known for being a calm guy — sometimes people think I’m too calm — and am I exasperated? Absolutely I’m exasperated because this is entirely unnecessary.”

Obama’s appearance on CNBC, which aired just after the markets closed at 4 p.m., came as the White House spent the day reaching out to business leaders in an effort to warn Republicans about the dangers of default. Treasury Secretary Jack Lew planned to join the president’s meeting with congressional leaders, in part to share details of how the 2011 threat of default hurt the U.S. economy.

Members of the Financial Services Forum met with Obama at the White House earlier in the day to express their concerns about a potential U.S. default on its debt obligations.

“There’s a consensus that we shouldn’t do anything that hurts this recovery,” Goldman Sachs CEO Lloyd Blankfein said as he left the meeting. “They shouldn’t use the threat of causing the U.S. to fail on its obligations to repay its debt as a cudgel.”

While “there’s precedent for a government shutdown, there’s no precedent for default,” he added. “We really haven’t seen this before and I’m not anxious to be part of the process to witness this.”

Obama told CNBC that if House Speaker John Boehner (R-Ohio) were to bring a clean government funding bill to the floor of the House, it would pass. But Boehner “has not been willing to say no to a faction of the Republican Party that are willing to burn the house down because an obsession over my health care initiative,” Obama said.

The president reiterated his position that he’s not open to negotiating with Republicans until the immediate crises over the budget and the debt ceiling are resolved.

“As soon as we get a clean piece of legislation that reopens the government… until we make sure that Congress allows Treasury to pay for things that Congress itself already authorized, we are not going to engage in a series of negotiations,” he said. “The reason… is very simple: If we get in the habit where a few folks, an extremist wing of one party, whether it’s Democrat or Republican, are allowed to extort concessions based on a threat of undermine the full faith and credit of the United States, then any president who comes after me, not just me, will find themselves unable to govern effectively. That is not something I’m going to allow to happen.”